Catalyst system with aluminum fluoride activator

ABSTRACT

Catalyst system suitable for polymerizing unsaturated monomers and comprising active constituents obtainable by reacting 
     A) a transition metal compound with 
     B) aluminum trifluoride, 
     C) a cation-forming compound and, if desired, 
     D) further components.

The present invention relates to a catalyst system suitable forpolymerizing unsaturated monomers and comprising active constituentsobtainable by reacting

A) a transition metal compound with

B) aluminum trifluoride,

C) a cation-forming compound and, if desired,

D) further components.

The present invention also relates to the use of aluminum trifluoride asactivator in a catalyst system, to a process for preparing a catalystsystem, to a process for preparing polymers based on monomers having C—Cdouble bond and/or C—C triple bond, and to the use of a catalyst systemfor forming carbon-carbon covalent bonds or carbon-heteroatom covalentbonds.

It is known that the following reactions, for example, can be performedin preparing metal compounds that are active in polymerization, such asmetallocenium ion catalysts:

a) metallocenedialkyl+strong cation-forming compound (Lewis acid), X.Yang, C. L. Stern. T. F. Marks, J. Am. Chem. Soc. 1991, 113, 3623-5

b) metallocenedialkyl+Brönsted acid with non-nucleophilic anion, EP 0591 756 (Idemitsu Kosan)

c) metallocene compound+aluminoxane EP 0 035 242 (BASF AG)

Reactions a) and b) have the common feature that they are severelyrestricted in terms of the choice of activator; that is, of the strongcation-forming compound and of the Brönsted acid with non-nucleophilicanion. Only very specific, preferably perfluoroaromatic, boron compoundslead to a usable activator. Reaction c) requires large amounts ofexpensive aluminoxane, which is a disruptive factor in the resultingpolymer.

There is therefore a desire to prepare active catalysts based oninexpensive, readily available and widely applicable activators. R.Taube in DD 265 150 A1 describes the polymerization of 1,3-butadiene inthe presence of a mixture of nickel cyclodecatriene or nickelacetylacetonate with aluminum triethyl and aluminum trifluoride. Thepolymerization of other monomers, especially alkenes or styrene and itsderivatives, and other catalysts, comprising aluminum trifluoride plus acation-forming compound, are not mentioned.

It is an object of the present invention to provide a catalyst systemwhich is not severely restricted in terms of the choice of activator.This means that even customary cation-forming compounds commonlyemployed in preparative organic chemistry, such as hexafluoroantimonicacid HSbF₆, antimony pentafluoride SbF₅, and trifluoromethanesulfonicacid CF₃SO₃H, could be used to generate transition metal catalysts. Inaddition, the catalyst system ought to be able to function per se as asupported catalyst or to be convertible to such a catalyst.

We have found that this object is achieved by the catalyst systemdefined at the outset, by the use of aluminum trifluoride in thecatalyst system defined at the outset, by a process for preparing thecatalyst system defined at the outset, by a process for preparingpolymers using the catalyst system defined at the outset, and by the useof the catalyst system defined at the outset for forming carbon-carboncovalent bonds or carbon-heteroatom covalent bonds.

Suitable transition metal compounds A) are in principle all those whichreact with components B), C) and, if used, D) chemically to form anactive catalyst.

Examples of highly suitable transition metal compounds A) are transitionmetal complexes with a ligand of the formulae F-I to F-IV

where the transition metal is selected from the elements Ti, Zr, Hf, Sc,V, Nb, Ta, Cr, Mo, W, Fe, CO, Ni, Pd and Pt or from an element of therare earth metals. Preference is given here to compounds of nickel andpalladium as the central metal.

E is an element from group 15 of the Periodic Table of the Elements (5thmain group), preferably N or P and, with particular preference, N. Thetwo atoms E in a molecule can be the same or different.

The radicals R^(1A) to R^(18A), which can be the same or different, areas follows:

R^(1A) and R^(4A) are independently of one another hydrocarbon radicalsor substituted hydrocarbon radicals, preferably those where the carbonadjacent to the element E is attached to at least two carbon atoms.

R^(2A) and R^(3A) are independently of one another hydrogen, hydrocarbonor substituted hydrocarbon radicals or else together form a ring systemwhich may also include one or more heteroatoms.

R^(6A) is hydrocarbon or substituted hydrocarbon radicals,

R^(5A) is hydrogen, hydrocarbon or substituted hydrocarbon radicals,

R^(6A) and R^(5A) may also together form a ring system.

R^(8A) is hydrocarbon or substituted hydrocarbon radicals,

R^(9A) is hydrogen, hydrocarbon or substituted hydrocarbon radicals,

R^(8A) and R^(9A) may also together form a ring system.

R^(7A) each independently of the others is hydrogen, hydrocarbon orsubstituted hydrocarbon radicals, it also being possible for tworadicals R^(7A) to form a ring system. n is an integer between 1 and 4,preferably 2 or 3.

R^(10A) and R^(14A) independently of one another are hydrogen,hydrocarbon or substituted hydrocarbon radicals.

R^(11A), R^(12A) and R^(13A) independently of one another are hydrogen,hydrocarbon or substituted hydrocarbon radicals, where two or moreradicals R^(11A), R^(12A) and R^(13A) may also together form a ringsystem.

R^(15A) and R^(18A) independently of one another are hydrogen,hydrocarbon or substituted hydrocarbon radicals.

R^(16A) and R^(17A) independently of one another are hydrogen,hydrocarbon or substituted hydrocarbon radicals.

Examples of particularly suitable compounds F-I to F-IV are:

Di(2,6-di-i-propylphenyl)-2,3-dimethyldiazabutadienepalladium dichlorideDi(di-i-propylphenyl)-2,3-dimethyldiazabutadienenickel dichlorideDi(2,6-di-i-propylphenyl)-dimethyldiazabutadienepalladium dimethylDi(2,6-di-i-propylphenyl)-2,3-dimethyldiazabutadienenickel dimethylDi(2,6-dimethylphenyl)-2,3-dimethyldiazabutadienepalladium dichlorideDi(2,6-dimethylphenyl)-2,3-dimethyldiazabutadienenickel dichlorideDi(2,6-dimethylphenyl)-2,3-dimethyldiazabutadienepalladium dimethylDi(2,6-dimethylphenyl)-2,3-dimethyldiazabutadienenickel dimethylDi(2-methylphenyl)-2,3-dimethyldiazabutadienepalladium dichlorideDi(2-methylphenyl)-2,3-dimethyldiazabutadienenickel dichlorideDi(2-methylphenyl)-2,3-dimethyldiazabutadienepalladium dimethylDi(2-methylphenyl)-2,3-dimethyldiazabutadienenickel dimethylDiphenyl-2,3-dimethyl-diazabutadienepalladium dichlorideDiphenyl-2,3-dimethyl-diazabutadienenickel dichlorideDiphenyl-2,3-dimethyl-diazabutadienepalladium dimethylDiphenyl-2,3-dimethyl-diazabutadienenickel dimethylDi(2,6-dimethylphenyl)-azanaphthenepalladium dichlorideDi(2,6-dimethylphenyl)-azanaphthenenickel dichlorideDi(2,6-dimethylphenyl)-azanaphthenepalladium dimethylDi(2,6-dimethylphenyl)-azanaphthenenickel dimethyl1,1′-Dipyridylpalladium dichloride 1,1′-Dipyridylnickel dichloride1,1′-Dipyridylpalladium dimethyl 1,1′-Dipyridylnickel dimethyl

Further particularly suitable transition metal compounds A) are thosehaving at least one cyclopentadienyl-type ligand, which are commonlyknown as metallocene complexes (two or more cyclopentadienyl-typeligands) or half-sandwich complexes (one cyclopentadienyl-type ligand).

Particularly suitable metallocene complexes are those of the formula

where

M is titanium, zirconium, hafnium, vanadium, niobium or tantalum or anelement from subgroup III of the Periodic Table or from the lanthanoids,

X is fluorine, chlorine, bromine, iodine, hydrogen, C₁-C₁₀-alkyl,C₆-C₁₅-aryl, alkylaryl having 1 to 10 carbons in the alkyl radical and 6to 20 carbons in the aryl radical, —OR⁶ or —NR⁶R⁷,

n is an integer between 1 and 3, n corresponding to the valence of Mminus 2,

and where

R⁶ and R⁷ are C₁-C₁₀-alkyl, C₆-C₁₅-aryl, alkylaryl, arylalkyl,fluoroalkyl or fluoroaryl having in each case 1 to 10 carbons in thealkyl radical and 6 to 20 carbons in the aryl radical,

R¹ to R⁵ are hydrogen, C₁-C₁₀-alkyl, 5-7 membered cycloalkyl which canin turn carry a C₁-C₁₀-alkyl as substituent, C₆-C₁₅-aryl or arylalkyl,where two adjacent radicals may if desired together be saturated orunsaturated cyclic groups having 4 to 15 carbons, or are Si(R⁸)₃ where

R⁸ is C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl or C₆-C₁₅-aryl,

and where the radicals

R⁹ to R¹³ are hydrogen, C₁-C₁₀-alkyl, 5-7-membered cycloalkyl which canin turn carry a C₁-C₁₀-alkyl substituent, C₆-C₁₅-aryl or arylalkyl andwhere two adjacent radicals may if desired together be saturated orunsaturated cyclic groups having 4 to 15 carbons, or are Si(R¹⁴)₃ where

R¹⁴ is C₁-C₁₀-alkyl, C₆-C₁₅-aryl or C₃-C₁₀-cycloalkyl,

or where the radicals R⁴ and Z together form a group —R¹⁵—A— in which

═BR¹⁶, ═AlR¹⁶, —Ge—, —Sn—, —O—, —S—, ═SO, ═SO₂, ═NR¹⁶, ═CO, ═PR¹⁶ or═P(O)R¹⁶,

where

R¹⁶, R¹⁷ and R¹⁸ are the same or different and are hydrogen, halogen,C₁-C₁₀-alkyl, C₁-C₁₀-fluoroalkyl, C₆-C₁₀-fluoroaryl, C₆-C₁₀-aryl,C₁-C₁₀-alkoxy, C₂-C₁₀-alkenyl, C₇-C₄₀-arylalkyl, C₈-C₄₀-arylalkenyl orC₇-C₄₀-alkylaryl, or where two adjacent radicals in each case form aring with the atoms linking them, and

M² is silicon, germanium or tin,

R¹⁹ is C₁-C₁₀-alkyl, C₆-C₁₅-aryl, C₃-C₁₀-cycloalkyl, alkylaryl orSi(R²⁰)₃,

R²⁰ is hydrogen, C₁-C₁₀-alkyl, C₆-C₁₅-aryl which may in turn besubstituted by C₁-C₄-alkyls, or is C₃-C₁₀-cycloalkyl

or where the radicals R⁴ and R¹² together form a group —R¹⁵—.

Preference among the metallocene complexes of the formula I is given to

The radicals X can be the same or different, but preferably are thesame.

Of the compounds of the formula Ia, particular preference is given tothose in which

M is titanium, zirconium or hafnium,

X is chlorine, C₁-C₄-alkyl or phenyl,

n is 2 and

R¹ to R⁵ are hydrogen or C₁-C₄-alkyl.

Of the compounds of the formula Ib, preference is given to those inwhich

M is titanium, zirconium or hafnium,

X is chlorine, C₁-C₄-alkyl or phenyl,

n is 2,

R¹ to R⁵ are hydrogen, C₁-C₄-alkyl or Si(R⁸)₃, and

R⁹ to R¹³ are hydrogen, C₁-C₄-alkyl or Si(R¹⁴)₃,

Particularly suitable compounds of formula Ib are those in which thecyclopentadienyl radicals are the same.

Examples of particularly suitable compounds include:

bis(cyclopentadienyl)zirconium dichloride,bis(pentamethylcyclopentadienyl)zirconium dichloride,bis(methylcyclopentadienyl)zirconium dichloride,bis(ethylcyclopentadienyl)zirconium dichloride,bis(n-butylcyclopentadienyl)zirconium dichloride andbis(trimethylsilylcyclopentadienyl)zirconium dichloride and thecorresponding dimethylzirconium compounds.

Particularly suitable compounds of the formula Ic are those in which

R¹ and R⁹ are the same and are hydrogen or C₁-C₁₀-alkyls,

R⁵ and R¹³ are the same and are hydrogen, methyl, ethyl, isopropyl ortert-butyl,

R², R³, R¹⁰ and R¹¹ are such that R³ and R¹¹ are C₁-C₄-alkyl R² and R¹⁰are hydrogen or else two adjacent radicals R² and R³ and also R¹⁰ andR¹¹ are together cyclic groups having 4 to 12 carbons,

M is titanium, zirconium or hafnium and

M² is silicon

X is chlorine, C₁-C₄-alkyl or phenyl.

Examples of particularly suitable complex compounds Ic include:

Dimethylsilanediylbis(cyclopentadienyl)zirconium dichloride,dimethylsilanediylbis(indenyl)zirconium dichloride,dimethylsilanediylbis(tetrahydroindenyl)zirconium dichloride,ethylenebis(cyclopentadienyl)zirconium dichloride,ethylenebis(indenyl)zirconium dichloride,ethylenebis(tetrahydroindenyl)zirconium dichloride,tetramethylethylene-9-fluorenylcyclopentadienylzirconium diechloride,dimethylsilanediylbis(3-tert-butyl-5-methylcyclopentadienyl)-zirconiumdichloride,dimethylsilanediylbis(3-tert-butyl-5-ethylcyclopentadienyl)-zirconiumdichloride, dimethylsilanediylbis(2-methylindenyl)zirconium dichloride,dimethylsilanediylbis(2-isopropylindenyl)zirconium dichloride,dimethylsilanediylbis(2-tert-butylindenyl)zirconium dichloride,diethylsilanediylbis(2-methylindenyl)zirconium dibromide,dimethylsilanediylbis(3-methyl-5-methylcyclopentadienyl)-zirconiumdichloride,dimethylsilanediylbis(3-ethyl-5-isopropylcyclopentadienyl)-zirconiumdichloride, dimethylsilanediylbis (2-ethylindenyl)zirconium dichloride,dimethylsilanediylbis(2-methylbenzindenyl)zirconium dichloridedimethylsilanediylbis(2-ethylbenzindenyl)zirconium dichloride,ethylphenylsilanediylbis(2-ethylbenzindenyl)zirconium dichloride,ethylphenylsilanediylbis(2-methylbenzindenyl)zirconium dichloride,diphenylsilanediylbis(2-methylbenzindenyl)zirconium dichloride,diphenylsilanediylbis(2-ethylbenzindenyl)zirconium dichloride, anddiphenylsilanediylbis(2-methylindenyl)hafnium dichloride and also thecorresponding dimethylzirconium compounds.

Further examples of suitable complex compounds Ic include:

Dimethylsilanediylbis(2-methyl-4-phenylindenyl)zirconium dichloride,dimethylsilanediylbis(2-methyl-4-[1-naphthylindenyl])zirconiumdichloride, Dimethylsilanediylbis(2-methyl-4-isopropylindenyl)zirconiumdichloride,Dimethylsilanediylbis(2-methyl-4,6-diisopropylindenyl)zirconiumdichloride, dimethylsilanediylbis(2-ethyl-4-phenylindenyl)zirconiumdichloride,Dimethylsilanediylbis(2-methyl-4-(para-4-butyl)phenylindenyl) zirconiumdichloride, and also the corresponding dimethylzirconium compounds.

Particularly suitable compounds of the formula Id are those in which

M is titanium or zirconium

X is chlorine, C₁-C₄-alkyl or phenyl.

and

R¹ to R³ and R⁵ are hydrogen, C₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl,C₆-C₁₅-aryl or Si(R⁸)₃ or where two adjacent radicals are cyclic groupshaving 4 to 12 carbons.

The synthesis of complex compounds of this kind can be carried out inaccordance with methods known per se, preference being given to thereaction of the correspondingly substituted cyclic hydrocarbon anionswith halides of titanium, zirconium, hafnium, vanadium, niobium ortantalum.

Examples of appropriate preparation techniques are described, interalia, in Journal of Organometallic Chemistry, 369 (1989), 359-370.

It is also possible to employ mixtures of different metallocenecomplexes.

Component B) is aluminum trifluoride. This is a known compound which isdescribed, for example, in Holleman-Wiberg, Lehrbuch d. Anorgan. Chemie,101st Ed. 1995, p. 1073 ff, Walter de Gruyter (Berlin, N.Y.). It can bein either crystalline or, preferably, amorphous form. A very suitableprocess for preparing amorphous aluminum trifluoride is the reaction ofaluminum triorganyls with, for example, boron trifluoride etherate, asdescribed in R. Taube, Macromol. Chem. 194 (1993), 1273-1288. thealuminum trifluoride B) can be isolated preparatively or prepared insitu for use.

The molar ratio of aluminum trifluoride B) to metal complex A) is from10,000:1 to 1:1, preferably from 100:1 to 1:1 and, with particularpreference, from 50:1 to 1:1.

The cation-forming compound C) is generally a Lewis acid (electricallyneutral or positively charged) or a Brönsted acid. Suitable neutralLewis acids are preferably those which form a non-nucleophilic anionafter reaction with the transition metal component A). Suitablepositively charged Lewis acids, and suitable Brönsted acids, arepreferably those having a conjugated anion with little or virtually nonucleophilicity.

One of the features of the invention is that both moderate and strongLewis acids, and anions of little to virtually no nucleophilicity, canbe used to generate a catalyst.

Suitable cation-forming compounds C) from the class of the moderateneutral and positively charged Lewis acids are compounds of elements ofGroups 13 to 15 of the Periodic Table of the Elements, of the formulaMetR′_(n), where Met is an element from groups 13 to 15 of the PeriodicTable of the Elements, R′ is inorganic or organic radicals which can bethe same or different, and n is an integer from 3 to 5 and representsthe valence of Met.

Preference is given in this context to compounds comprising elements ofgroups 13 and 15 with only halogen atoms as substituents. Particularpreference is given to boron trifluoride and antimony pentafluoride.

Positively charged Lewis acids can be selected, for example, fromcompounds of the formulae [MetR′_(n+1)]^(⊕)[An]^(⊖) or[MetR′_(n−1)]^(⊕)[An]^(⊖), where Met is an element from groups 13 to 16of the Periodic Table of the Elements, R′ is inorganic or organicradicals which can be the same or different, and n is an integer from 2to 5 which represents the valence of Met. The nature of thecorresponding anion [An]^(⊖) is not critical per se, with anions such asboron tetrafluoride and antimony hexafluoride, for example, havingproven suitable. Positively charged Lewis acids with exclusively organicsubstituents are preferred. Particular preference is given to compoundssuch as C(C₆H₅)₃ ^(⊕)BF₄ ^(⊖) or O(CH₃)₃ ^(⊕)BF₄ ^(⊖), for example.

Suitable compounds from the class of the Brönsted acids with an anion oflow nucleophilicity (b) are those in which the anion is of the formulaMetR′_(n+1) ^(⊖) where Met is an element from groups 13 to 15 of thePeriodic Table of the Elements, R′ is inorganic or organic radicalswhich can be the same or different, and n is an integer from 3 to 5 andrepresents the valence of Met. Preference is given to anions carryingexclusively halogen substituents on the central element. Compounds suchas HBF₄ and HSbF₆ are particularly preferred. These compounds can alsobe in the form of etherates.

A further class of anions of low nucleophilicity which can be used isderived from the formula R′SO₃ ^(⊕). In this formula R′ is an inorganicor organic radical, preferably an organic C₁-C₁₀-alkyl or C₆-C₂₀-arylradical, where preferably at least some of the hydrogen atoms can besubstituted by halogen atoms, preferably by fluorine atoms. Examples ofparticularly preferred compounds of this class are acids R′SO₃-H, suchas fluorosulfonic, phenylsulfonic, trifluoromethylsulfonic andpentafluorophenylsulfonic acid.

Strong, neutral Lewis acids as component C) are compounds of the formula(II)

M³X¹X²X³  II

where

M³ is an element from main group III of the Periodic Table, especiallyB, Al or Ga, preferably B,

X¹, X² and X³ are hydrogen, C₁-C₁₀-alkyl, C₆-C₁₅-aryl, alkylaryl,arylalkyl, haloalkyl or haloaryl each having 1 to 10 carbons in thealkyl radical and 6 to 20 carbons in the aryl radical, or are fluorine,chlorine, bromine or iodine, and in particular are haloaryls, preferablypentafluorophenyl.

Particular preference is given to compounds of the formula II in whichX¹, X² and X³ are the same, preferably tris(pentafluorophenyl)borane.

Ionic compounds as component C), having strong Lewis-acid cations, arecompounds of the formula III

[(Y^(a+))Q₁Q₂ . . . Q_(z)]^(d+)  III

where

Y is an element of main groups I to VI or of subgroups I to VIII of thePeriodic Table,

Q₁ to Q_(z) are radicals bearing a single negative charge, such asC₁-C₂₈-alkyl, C₆-C₁₅-aryl, alkylaryl, arylalkyl, haloalkyl, haloaryleach having 6 to 20 carbons in the aryl and 1 to 28 carbons in the alkylradical, C₃-C₁₀-cycloalkyl, which can be unsubstituted or substituted byC₁-C₁₀-alkyl groups, or are halogen, C₁-C₂₈-alkoxy, C₆-C₁₅-aryloxy,silyl or mercaptyl,

a is an integer from 1 to 6 and

z is an integer from 0 to 5,

d being the difference a-z but being greater than or equal to 1.

Carbonium cations, oxonium cations and sulfonium cations, and alsocationic transition metal complexes, are particular suitable. Mentionmay be made in particular of the triphenylmethyl cation, the silvercation and the 1,1′-dimethylferrocenyl cation. They preferably havenoncoordinating counterions, especially boron compounds as are alsomentioned in WO 91/09882, preferably tetrakis(pentafluorophenyl)borate.

Ionic compounds as component C) with Brönsted acids as cations andpreferably likewise noncoordinating counterions are mentioned in WO91/09882; a preferred cation is N,N-dimethylanilinium.

The amount of metallocenium ion-forming compound is preferably from 0.1to 10 equivalents based on the transition metal component A).

Component C) can also consist of or comprise an aluminoxane.

Compounds particularly suitable as the cation-forming component C) areopen-chain or cyclic alumoxane compounds of the formula V or VI

where R²⁴ is a C₁-C₄-alkyl, preferably methyl or ethyl, and m is aninteger from 5 to 30, preferably from 10 to 25.

These oligomeric alumoxane compounds are customarily prepared byreacting a solution of trialkylaluminum with water as is described,inter alia, in EP-A 284 708 and U.S. Pat. No. 4,794,096.

In general, the resulting oligomeric alumoxane compounds are in the formof mixtures of both linear and cyclic chain molecules of various length,so that m should be regarded as an average value. The alumoxanecompounds can also be present in a mixture with other metal alkyls,preferably with aluminum alkyls.

As component C) it is additionally possible to employ aryloxyalumoxanesas described in U.S. Pat. No. 5,391,793, aminoaluminoxanes as describedin U.S. Pat. No. 5,371,260, aminoaluminoxane hydrochlorides as describedin EP-A 633 264, siloxyaluminoxanes as described in EP-A 621 279, ormixtures thereof.

It has been found advantageous to use the transition metal compound A)and the oligomeric alumoxane compound in amounts such that the atomicratio between aluminum from the oligomeric alumoxane compound and thetransition metal from the transition metal compound A is from 1:1 to10⁶:1, preferably from 1:1 to 10⁴:1, and, in particular, from 1:1 to10:1.

As component D), the catalyst system of the invention may also include,if desired, an organometallic compound, preferably a metal compound ofthe formula IV

M¹(R²¹)_(r)(R²²)_(s)(R²³)_(t)  IV

where

M¹ is an alkali metal, an alkaline earth metal or a metal from maingroup III of the Periodic Table, i.e., boron, aluminum, gallium, indiumor thallium,

R²¹ is hydrogen, C₁-C₁₀-alkyl, C₆-C₁₅-aryl, alkylaryl or arylalkylhaving in each case 1 to 10 carbons in the alkyl radical and 6 to 20carbons in the aryl radical,

R²² and R²³ are hydrogen, halogen, C₁-C₁₀-alkyl, C₆-C₅-aryl, alkylaryl,arylalkyl or alkoxy having in each case 1 to 10 carbons in the alkylradical and 6 to 20 carbons in the aryl radical,

r is an integer from 1 to 3

and

s and t are integers from 0 to 2, the sum r+s+t corresponding to thevalence of M¹.

Where component D) is present together with A) and/or C), it is not thesame as components A) and, especially, C).

Among the metal compounds of formula IV preference is given to those inwhich

M¹ is lithium, magnesium or aluminum and

R²¹ to R²³ are C₁-C₁₀-alkyl.

Particularly preferred metal compounds of the formula IV aren-butyllithium, n-butyl-n-octylmagnesium, n-butyl-n-heptyl-magnesium,tri-n-hexylaluminum, tri-isobutylaluminum, triethylaluminum andtrimethylaluminum.

If component D) is employed it is present in the catalyst system in anamount of preferably from 800:1 to 1:1, in particular from 500:1 to 50:1(molar proportion of M¹ from IV to transition metal M from I).

In addition to A), B), C) and, if used, D), the catalyst system maycomprise a support substance.

Examples of suitable support substances are organic polymers, butpreferably porous inorganic materials.

The support materials employed are preferably finely divided supportshaving a particle diameter in the range from 0.1 to 1000 μn preferablyfrom 10 to 300 μm, and, in particular, from 30 to 70 μm. Examples ofsuitable organic supports are finely divided polymers, such as finelydivided polyethylene or polypropylene. Examples of suitable inorganicsupports are aluminum trioxide, silicon dioxide, titanium dioxide ormixed oxides thereof, aluminum phosphate or magnesium chloride. It ispreferred to employ silica gels of the formula SiO₂.a Al₂O₃, in which ais a number from 0 to 2, preferably from 0 to 0.5. The support particlescan be used in granular form and also spray-dried in microscopic form.Products of this kind are obtainable commercially, examples being SilicaGel 332 from Grace or ES 70×to from Crosfield.

Preferred inorganic support materials are acidic, inorganic metal oxidesor semimetal oxides of very high porosity, which are described, forexample, in the prior German Patent Application 197 20 980.7, especiallyon page 3, line 45 to page 5, line 11.

The support materials may have been pretreated thermally or chemically(with metal alkyl compounds, for example) in order to obtain a certainprofile of properties of the support (for example, water content and/orhydroxyl content).

The catalyst system of the invention is generally obtained by reactingaluminum fluoride with a transition metal compound A) which has beenbrought into contact beforehand with a cation former C). This reactioncan be conducted in homogeneous liquid phase or else in the presence ofa support material, generally with the use of organic solvents assuspension media. The resulting compound can be employed as a catalystdirectly, in suspension. An alternative possibility is to isolate thecompound and to employ it per se as a catalyst in, for example,gas-phase processes; otherwise, it can be resuspended after isolationand then employed as a catalyst.

The aluminum fluoride B) can also be prepared in situ (for example, byreacting an aluminum alkyl compound with boron trifluoride) and thenbrought into contact, in the presence or absence of a support material,with the product of reaction of transition metal compound A) and cationformer C). The reaction of the transition metal compound A) with thecation former C) can also be conducted in the presence of aluminumfluoride B) and in the presence or absence of a support material.

The catalyst system of the invention is employed to polymerize monomershaving a C—C double bond or a C—C triple bond. Said C—C double or C—Ctriple bond, or both, can be arranged either at the ends of or withinthe module, either exocyclically or endocyclically. Preferred monomerswith C—C triple bond are C₂-C₁₀-alk-1-ynes, such as ethyne, propyne,1-butyne, 1-hexyne, and also phenylacetylene. Preferred monomers with aC—C double bond are C₂-C₂₀-alk-1-enes and C₈-C₂₀ vinylaromaticcompounds. The polymerization process of the Invention is preferablyemployed to polymerize or copolymerize C₂-C₁₂-alk-1-enes. PreferredC₂-C₁₂-alk-1-enes are ethylene, propylene, 1-butene, 1-pentene,4-methyl-1-pentene, 1-hexene, 1heptene or 1-octene, and vinylaromaticmonomers, such as styrene, p-methylstyrene or 2,4-dimethylstyrene, ormixtures of these C₂-C₁₂-alk-1-enes. Particular preference is given tohomopolymers or copolymers of ethylene or of propylene, the proportionof ethylene or-propylene in the copolymers being at least 50 mol %. Inthe case of ethylene copolymers preference is given to those comprisingpropylene, 1-butene, 1-hexene, or 1-octene, or mixtures thereof, asfurther monomers. In the case of propylene copolymers, the copolymersconcerned are in particular those comprising ethylene or 1-butene, ormixtures of these, as further monomers.

Preference is given to using the polymerization process of the inventionto prepare polymers which comprise from 50 to 100 mol % of ethylene andfrom 0 to 50 mol %, in particular from 0 to 30 mol %, ofC₃-C₁₂-alk-1-enes.

Preference is also given to those polymers which comprise from 50 to 100mol % of propylene, from 0 to 50 mol %, in particular from 0 to 30 mol%, of ethylene and from 0 to 20 mol %, in particular from 0 to 10 mol %,of C₄-C₁₂-alk-1-enes.

The sum of the molar percentages is always 100.

The polymerization can be conducted by the techniques customary forpolymerizing olefins, such as solution, suspension, stirred gas-phase orgas-phase fluidized-bed techniques, continuously or batchwise. Assolvents or suspension media it is possible to use inert hydrocarbons,such as isobutane, or else the monomers themselves. Particularlysuitable techniques for preparing the polymers are the suspensiontechnique and the gas-phase technique (stirred gas phase, gas-phasefluidized bed).

Suitable reactors include continuously operated stirred vessels, loopreactors or fluidized-bed reactors, it also being possible if desired touse two or more reactors connected one after another in a row (reactorcascade).

The polymerization by means of the process of the invention is generallycarried out at temperatures in the range from −50 to 300° C., preferablyfrom 0 to 150° C., and under pressures of generally from 0.5 to 3000bar, preferably from 1 to 80 bar. In the polymerization process of theinvention it is advantageous to establish residence times of therespective reaction mixtures of from 0.5 to 5 hours, in particular from0.7 to 3.5 hours. In the course of the polymerization it is alsopossible to use, inter alia, antistats and molecular mass regulators, anexample being hydrogen.

Apart from for polymerization, the catalyst system of the invention canalso be used for stoichiometric or catalytic, nonrepetitivecarbon-carbon linkage, and for reducing carbonyl groups >C═O or iminogroups >C═NH with carbon radicals, hydrides or amides, and also in theDiels-Alder reaction and in the hydrogenation of unsaturatedcarbon-carbon, carbon-heteroatom and heteroatom-heteroatom bonds withhydrogen and/or hydrides.

In general, these reactions proceed in the low molecular mass range andthey generally lead to products having a molecular weight of less thanabout 1000.

EXAMPLES Example 1 Preparing Amorphous AlF₃—(0.4-0.6 Toluene)

A 1 l three-necked flask was charged with a solution of 14.9 g (105mmol) of BF₃.OEt₂ in 150 ml of toluene, and 11.4 g (100 mmol) of AlEt₃in 150 ml of toluene were added slowly via a dropping funnel withpressure compensation, with stirring. Interim coagulation was removed byvigorous shaking. The precipitate was isolated by decanting and wasdried under reduced pressure at 80° C. This gave 12 g of a fine whitepowdery substance.

Example 2 Preparing the Catalysts

2.1 Preparation from Metallocene Dialkyls

A 100 ml three-necked flask was charged with a solution of 1 g (3.6mmol) of Cp₂ZrMe₂ in 20 ml of toluene, and 950 mg (4 mmol) ofhexafluoroantimonic acid were added. The solution took on a red color.About 15 g of the AlF₃ obtained in Ex. 1 were added, and the toluene wasremoved under reduced pressure. This gave about 16 g of a free-flowingpowder (catalyst 1).

2.2 Preparation from Metallocene Dichloride

A 100 ml of three-necked flask was charged with a solution of 1 g (3.1mmol) of Cp₂ZrCl₂ in 20 ml of toluene, and 750 mg (3,5 mmol) ofantimonypentafluoride (Aldrich) were added. The solution took on a redcolor. About 15 g of the AlF₃ obtained in Ex. 1 were added and thetoluene was removed under reduced pressure. This gave about 15.5 g of afree-flowing powder (catalyst 2)

2.3 Preparation of a Catalyst fromdimethylsilylenebis(2-methyl-4,5-benzoindenyl) zirconocene dichloride

A 500 ml three-necked flask was charged with a solution of 0.5 g (0.9mmol) of dimethylsilylenebis(2-methyl-4,5-benzoindenyl)-zirconocenedichloride in 300 ml of toluene, and 215 mg (1 mmol) of antimonypentafluoride (Aldrich) were added. The solution took on a red color.About 5 g of the AlF₃ obtained in Example 1 were added and the toluenewas removed under reduced pressure. This gave about 5.5 g of afree-flowing powder (catalyst 3).

Example 3 Polymerizing with the Catalysts obtained

3.1 Homopolymerization of Ethylene

4.5 l of isobutane in 80 mg of butyllithium (as a solution in heptane)were charged to a stirred 10 l steel autoclave which had been carefullyflushed with nitrogen and conditioned at the polymerization temperatureof 70° C. beforehand. Then 200 mg of catalyst 1 or 2 were flushed inwith a further 0.5 l of isobutane, and ethylene was injected to a totalpressure of 38 bar. The pressure within the autoclave was kept constantby adding further ethylene. After 90 minutes, the polymerization wasdiscontinued by letting down the autoclave. The polymer was obtained inthe form of a free-flowing coarse powder. Yield: 1.4 kg (catalyst 1),1.5 kg (catalyst 2).

3.2 Copolymerization of Ethylene and 1-Hexene

4.5 l of isobutane, 400 ml of 1-hexene and 150 mg of butyllithium (as asolution in heptane) were charged to a stirred 10 l steel autoclavewhich had been carefully flushed with nitrogen and conditioned at thepolymerization temperature of 70° C. beforehand. Then 200 mg of catalyst1 or 2 were flushed in with a further 0.5 l of isobutane, and ethylenewas injected to a total pressure of 38 bar. The pressure within theautoclave was kept constant by adding further ethylene. After 90minutes, the polymerization was discontinued by letting down theautoclave. The polymer was obtained in the form of a free-flowing coarsepowder. Yield: 1.8 kg (catalyst 1), 1.7 kg (catalyst 2).

3.3 Propylene Homopolymerization

100 g of initial polymer charge were placed in an autoclave under anitrogen countercurrent. At a slow stirring speed (100 rpm) theautoclave was flushed with three times 5 bar of nitrogen. Then mmol ofaluminum alkyl (9 ml of 2-molar TiBal and 1 ml of 2-molar DiBAHsolutions in heptane) were added via the feed port, under the nitrogencountercurrent, and the autoclave was again flushed. The catalyst (200mg of catalyst 3) was introduced in solid form via the feed port, usingan introduction tube, in the nitrogen countercurrent. Then 7 l of liquidpropylene were placed in the autoclave. The autoclave was heated to70-75° C. and the stirrer speed was increased. On reaching the targettemperature (65° C.) polymerization was conducted for 90 minutes. Theautoclave was then let down and the product was discharged through abottom outlet valve. Said product comprised 750 g of polypropylene, or650 g after deducting the amount of the initial charge, corresponding toa productivity of 3.25 kg of propylene/g of catalyst.

Example 4 Preparing the Catalyst

350 mg (0.1 mmol) of bis-indenylzirconium dimethyl are dissolved in 30ml of absolute toluene. 150 mg (0.1 mmol) of trifluoromethanesulfonicacid (2 molar in toluene) are added. 1.7 g (20 mmol) of amorphous AlF₃are added to the reaction mixture. The reaction mixture is stirred atroom temperature for 30 minutes.

Ethylene polymerization:

A 1 l autoclave is charged with 80 mg of aluminum triethyl (as asolution in heptane) and 400 ml of isobutane. Ethylene is injected to apressure of 40 bar, the autoclave is conditioned at 70° C., and then 3ml of the above suspension are added via an airlock. After 65 minutesthe polymerization was discontinued by letting down the autoclave. Thisgave 45 g of polyethylene, η value: 14.7 dl/g.

Example 5 Preparing the Catalyst

350 mg (1 mmol) of bis-indenylzirconium dimethyl are dissolved in 30 mlof absolute toluene. 150 mg (1 mmol) of trifluoromethanesulfonic acid (2molar in toluene) are added and are dissolved at 80° C. for 30 minutes.1.7 g (20 mmol) of amorphous AlF₃ are added to the reaction mixture. Thereaction mixture is stirred at 90° C. for 1 h. Then 10 g of silica gel(from Grace SG 332, purified by heating at 130° C. and treated withTiBAL) are added. The solvent is removed by filtration and the residueis washed with heptane. Drying under reduced pressure gives 11.9 g of afree-flowing solid.

Ethylene Polymerization:

A 1 l autoclave is charged with 120 mg of aluminum triethyl (as asolution in heptane) and 400 ml of isobutane. Ethylene is injected to apressure of 40 bar, the autoclave is conditioned at 70° C., and then 335mg of the supported catalyst are added via an airlock. After 90 minutesthe polymerization was discontinued by letting down the autoclave. Thisgave 90 g of polyethylene, η value: 49.5 dl/g.

Example 6 Preparing the Catalyst

540 mg (0.1 mmol) ofdi(2,6-diisopropylphenyl)-2,3-dimethyldiazabutadienepalladium dimethylwere dissolved in 30 ml of absolute toluene. 150 mg (0.1 mmol) oftrifluoromethanesulfonic acid (2 molar in toluene) were added. 1.7 g (20mmol) of amorphous AIF₃ were added to the reaction mixture. The reactionmixture was stirred at room temperature for 30 minutes.

Ethylene polymerization

A 1 l autoclave was charged with 80 mg of aluminum triethyl (as asolution in heptane) and 400 ml of isobutane. Ethylene was injected to apressure of 40 bar, the autoclave is conditioned at 70° C., and then 3ml of the above suspension were added via an airlock. After 65 minutesthe polymerization was discontinued by letting down the autoclave. Thisgave 31 g of viscous polyethylene, with M_(w)=40,000 and M_(w)/M_(n)=2.

TABLE Polymerizations with AlF₃-comprising catalysts Cation Support/Polymerization Cat. Ex. Complex former Activator Monomer(s)³⁾ ComponenteD)⁴⁾ Examples 2.1 Cp₂ZrMe₂ HSbF₆ AlF₃ C₂═ n-BuLi 3.1 2.2 Cp₂ZrCl₂ SbF₅AlF₃ C₂═ n-BuLi 3.1 2.3 SiMe₂(2-Me- SbF₅ AlF₃ C₃═ TiBAL/DiBAH 3.3BInd)₂ZrCl₂ ¹⁾ 2.1 Cp₂ZrMe₂ HSbF₆ AlF₃ C₂═/C₆═ n-BuLi 3.2 2.2 Cp₂ZrCl₂SbF₅ AlF₃ C₂═/C₆═ n-BuLi 3.2 4 Ind₂ZrMe₂ ²⁾ CF₃SO₃H AlF₃ C₂═ AlEt₃ 4 5Ind₂ZrMe₂ ²⁾ CF₃SO₃H AlF₃ + SiO₂ C₂═ AlEt₃ 5 6 diazabutadie- CF₃SO₃HAlF₃ C₂═ AlEt₃ 6 ne PdMe₂ ¹⁾Dimethylsilylenebis(2-methyl-4,5-benzoindenyl) zirconocene dichloride ²⁾Bis(indenyl)zirconium dimethyl ³⁾C₂═ = ethylene, C₃═ = propylene, C₆═ = 1-hexene⁴⁾TiBAL = Triisobutylaluminum, DiBAH = Diisobutylaluminum hydride

We claim:
 1. A catalyst system suitable for polymerizing unsaturatedmonomers and consisting essentially of active constituents obtained byreacting A) a transition metal compound selected from the groupconsisting of complexes with ligands comprising an element from group 15of the Periodic Table of the Elements where the transition metal isselected from the elements Ti, Zr, Hf, Sc, V, Nb, Ta, Cr, Mo, W, Fe, Co,Ni, Pd or Pt or from an element of the rare earth metals, of metallocenecomplexes and of half-sandwich complexes with B) aluminum trifluoride,C) a cation-forming compound other than B), selected from the groupconsisting of moderate and positively charged Lewis acids of the formulaMetR′_(n), [MetR′_(n+1)]⁺[An]⁻ or [MetR′_(n−1)]⁺[An]⁻  where Met is anelement from groups 13 to 16 of the Periodic Table of Elements, R′ isinorganic or organic radicals which can be the same or different, n isan integer from 3 to 5 and represents the valence of Met, and [An]⁻ isan anion, Brnsted acids with an anion of low nucleophilicity, of theformula [MetR′_(n+1)]⁻,  where Met is an element from groups 13 to 15 ofthe Periodic Table of Elements, R′ is inorganic or organic radicalswhich can be the same or different, and n is an integer from 2 to 5 andrepresents the valence of Met, anions of low nucleophilicity, of theformula R′SO₃ ⁻,  where R′ is an inorganic or organic radical, strongneutral Lewis acids of the formula II M³X¹X²X³   II  where M³ is anelement from the main group III of the Periodic Table, and X¹, X² and X³are hydrogen, C₁- to C₁₀-alkyl, C₆- to C₁₅-aryl, alkylaryl, arylalkyl,haloalkyl or haloaryl having in each case 1 to 10 carbon atoms in thealky radical and 6 to 20 carbon atoms in the aryl radical, or arefluorine, chlorine, bromine or iodine, and ionic compounds having strongLewis-acid cations, of the formula III [(Y^(a+))Q₁Q₂ . . .Q_(z)]^(d+)  III where Y is an element of main groups I to VI or ofsubgroups I to VIII of the Periodic Table, Q₁ to Q_(z) are radicalsbearing a single negative charge, selected from the group consisting ofC₁-C₂₈-alkyl, C₆- to C₁₅-aryl, alkylaryl, arylalkyl, haloalkyl, haloaryleach having 6 to 20 carbon atoms in the aryl and 1 to 28 carbon atoms inthe alkyl radical, C₃- to C₁₀-cycloalkyl, which can be unsubstituted orsubstituted by C₁- to C₁₀-alkyl groups, or are halogen, C₁- toC₂₈-alkoxy, C₆- to C₁₅-aryloxy, silyl and mercaptyl groups a is aninteger from 1 to 6 and z is an integer from 0 to 5, d being thedifference a-z but being greater than or equal to 1, and, optionally, D)one or more metal compounds of the formula IVM¹(R²¹)_(r)(R²²)_(s)(R²³)_(t)  IV where M¹ is an alkali metal, analkaline earth metal or a metal from group 13 of the Periodic Table, R²¹is hydrogen, C₁-C₁₀-alkyl, C₆-C₁₅-aryl, alkylaryl or arylalkyl having ineach case 1 to 10 carbon atoms in the alkyl radical and 6 to 20 carbonatoms in the aryl radical, R²² and R²³ are hydrogen, halogen,C₁-C₁₀-alkyl, C₆-C₁₅-aryl, alkylaryl, arylalkyl or alkoxy having in eachcase 1 to 10 carbon atoms in the alkyl radical and 6 to 20 carbon atomsin the aryl radical r is an integer from 1 to 3, and s and t areintegers from 0 to 2, the sum r+s+t corresponding to the valence of M¹.2. A catalyst system as claimed in claim 1, where the aluminumtrifluoride is amorphous.
 3. A catalyst system as claimed in claims 1,where the transition metal compound used is of the formula I

where M is titanium, zirconium, hafnium, vanadium, niobium or tantalumor an element from subgroup III of the Periodic Table or from thelanthanoids, X is fluorine, chlorine, bromine, iodine, hydrogen,C₁-C₁₀-alkyl, C₆-C₁₅-aryl, alkylaryl having 1 to 10 carbons in the alkylradical and 6 to 20 carbons in the aryl radical, —OR⁶ or —NR⁶R⁷, n is aninteger between 1 and 3, n corresponding to the valence of M minus 2,and where R⁶ and R⁷ are C₁-C₁₀-alkyl, C₆-C₁₅-aryl, alkylaryl, arylalkyl,fluoroalkyl or fluoroaryl having in each case 1 to 10 carbons in thealkyl radical and 6 to 20 carbons in the aryl radical, R¹ to R⁵ arehydrogen, C₁-C₁₀-alkyl, 5-7 membered cycloalkyl which can in turn carrya C₁-C₁₀-alkyl as substituent, C₆-C₁₅-aryl or arylalkyl, where twoadjacent radicals may if desired together be saturated or unsaturatedcyclic groups having 4 to 15 carbons, or are Si(R⁸)₃ where R⁸ isC₁-C₁₀-alkyl, C₃-C₁₀-cycloalkyl or C₆-C₁₅-aryl,

and where the radicals R⁹ to R¹³ are hydrogen, C₁-C₁₀-alkyl,5-7-membered cycloalkyl which can in turn carry a C₁-C₁₀-alkylsubstituent, C₆-C₁₅-aryl or arylalkyl and where two adjacent radicalsmay if desired together be saturated or unsaturated cyclic groups having4 to 15 carbons, or are Si(R¹⁴)₃ where R¹⁴ is C₁-C₁₀-alkyl, C₆-C₁₅-arylor C₃-C₁₀-cycloalkyl, or where the radicals R⁴ and Z together form agroup —R¹⁵—A— in which

═BR¹⁶, ═AlR¹⁶, —Ge—, —Sn—, —O—, —S—, ═SO, ═SO₂, ═NR¹⁶, ═CO, ═PR¹⁶ or═P(O)R¹⁶, where R¹⁶, R¹⁷ and R¹⁸ are the same or different and arehydrogen, halogen, C₁-C₁₀-alkyl, C₁-C₁₀-fluoroalkyl, C₆-C₁₀-fluoroaryl,C₆-C₁₀-aryl, C₁-C₁₀-alkoxy, C₂-C₁₀-alkenyl, C₇-C₄₀-arylalkyl,C₈-C₄₀-arylalkenyl or C₇-C₄₀-alkylaryl, or where two adjacent radicalsin each case form a ring with the atoms linking them, and M² is silicon,germanium or tin,

R¹⁹ is C₁-C₁₀-alkyl, C₆-C₁₅-aryl, C₃-C₁₀-cycloalkyl, alkylaryl orSi(R²⁰)₃, R²⁰ is hydrogen, C₁-C₁₀-alkyl, C₆-C₁₅-aryl which may in turnbe substituted by C₁-C₄-alkyls, or is C₃-C₁₀-cycloalkyl or where theradicals R⁴ and R¹² together form a group —R¹⁵—.
 4. A catalyst system asclaimed in claim 1, where component D) is an organometallic compound. 5.A process for preparing a catalyst system suitable for polymerizingunsaturated monomers, by reacting active constituents consistingessentially of A) a transition metal compound selected from the groupconsisting of complexes with ligands comprising an element from-group 15of the Periodic Table of the Elements where the transition metal isselected from the elements Ti, Zr, Hf, Sc, V, Nb, Ta, Cr, Mo, W, Fe, Co,Ni, Pd or Pt or from an element of the rare earth metals, metallocenecomplexes and half-sandwich complexes with B) aluminum trifluoride, C) acation-forming compound other than B),  selected from the groupconsisting of  moderate and positively charged Lewis acids of theformula MetR′_(n), [MetR′_(n+1)]⁺[An]⁻ or [MetR′_(n−1)]⁺[An]⁻  where Metis an element from groups 13 to 16 of the Periodic Table of Elements, R′is inorganic or organic radicals which can be the same or different, nis an integer from 3 to 5 and represents the valence of Met, and [An]⁻is an anion, Bronsted acids with an anion of low nucleophilicity, of theformula [MetR′_(n+1)]⁻,  where Met is an element from groups 13 to 15 ofthe Periodic Table of Elements, R′ is inorganic or organic radicalswhich can be the same or different, and n is an integer from 2 to 5 andrepresents the valence of Met, anions of low nucleophilicity, of theformula R′SO₃ ⁻,  where R′ is an inorganic or organic radical, strongneutral Lewis acids of the formula II M³X¹X²X³  II  where M³ is anelement from the main group III of the Periodic Table, and X¹, X² and X³are hydrogen, C₁- to C₁₀-alkyl, C₆- to C₁₅-aryl, alkylaryl, arylalkyl,haloalkyl or haloaryl having in each case 1 to 10 carbon atoms in thealky radical and 6 to 20 carbon atoms in the aryl radical, or arefluorine, chlorine, bromine or iodine, and ionic compounds having strongLewis-acid cations, of the formula III [(Y^(a+))Q₁Q₂ . . .Q_(z)]^(d+)  III where Y is an element of main groups I to VI or ofsubgroups I to VII of the Periodic Table, Q₁ to Q_(z) are radicalsbearing a single negative charge, selected from the group consisting ofC₁-C₂₈-alkyl, C₆- to C₁₅-aryl, alkylaryl, arylalkyl, haloalkyl, haloaryleach having 6 to 20 carbon atoms in the aryl and 1 to 28 carbon atoms inthe alkyl radical, C₃- to C₁₀-cycloalkyl, which can be unsubstituted orsubstituted by C₁- to C₁₀-alkyl groups, or are halogen, C₁- toC₂₈-alkoxy, C₆- to C₁₅-aryloxy, silyl or mercaptyl groups a is aninteger from 1 to 6 and z is an integer from 0 to 5, d being thedifference a-z but being greater than or equal to 1, and, optionally, D)one or more metal compounds of the formula IVM¹(R²¹)_(r)(R²²)_(s)(R²³)_(t)  IV  where M¹ is an alkali metal, analkaline earth metal or a metal from group 13 of the Periodic Table, R²¹is hydrogen, C₁-C₁₀-alkyl, C₆-C₁₅-aryl, alkylaryl or arylalkyl having ineach case 1 to 10 carbon atoms in the alkyl radical and 6 to 20 carbonatoms in the aryl radical, R²² and R²³ are hydrogen, halogen,G₁-C₁₀-alkyl, C₆-C₁₅-aryl, alkylaryl, arylalkyl or alkoxy having in eachcase 1 to 10 carbon atoms in the alkyl radical and 6 to 20 carbon atomsin the ary radical r is an integer from 1 to 3, and s and t are integersfrom 0 to 2, the sum r+s+t corresponding to the valence of M¹.
 6. Aprocess for preparing polymers based on monomers with C—C double bondand/or C—C triple bond, by polymerizing these monomers in the presenceof a catalyst system as claimed in claims
 1. 7. A process for preparingpolymers as claimed in claim 6, where the monomers with C—C double bondare selected from the group consisting of C₂-C₂₀-alk-1-enes and C₈-C₂₀vinylaromatic compounds.